Method and apparatus for an insulating glazing unit and compliant seal for an insulating glazing unit

ABSTRACT

A vacuum insulating glazing unit (VIGU) comprises two or more glass lites (panes) spaced apart from one another and hermetically bonded to an edge seal assembly therebetween. The resulting cavity between the lites is evacuated to create at least one insulating vacuum cavity within which are disposed a plurality of stand-off members to maintain separation between the lites. The edge seal assembly is preferably compliant in the longitudinal (i.e., edgewise) direction to allow longitudinal relative motion between the two lites (e.g., from thermal expansion). The longitudinal compliance may be obtained by imprinting a three-dimensional pattern into the edge seal material. The edge seal assembly is preferably bonded to the lites with a first bond portion that is hermetic and a second bond portion that is load-resistant. Methods for producing VIGUs and/or compliant edge seal assemblies and VIGU and edge seal apparatus are disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/141,485 filed Apr. 28, 2016, which is a continuation of U.S.application Ser. No. 13/464,951 filed May 4, 2012, which claims thebenefit of U.S. provisional application No. 61/482,701 filed on May 5,2011. application Ser. Nos. 15/141,485, 13/464,951 and 61/482,701 areincorporated-by-reference herein in their entirety.

This invention was made with government support under Contract No.DE-EE0004024 awarded by the Department of Energy. The Government hascertain rights in this invention.

TECHNICAL FIELD

The following disclosure relates generally to insulating glazingapparatus (including insulated glazing units and vacuum insulatingglazing units) having spaced-apart glazing panes. More specifically, itrelates to insulating glazing apparatus having compliant seals forproviding an airtight seal between the spaced-apart panes of aninsulating glazing apparatus, apparatus comprising such seals, andmethods for manufacture of same.

BACKGROUND

Insulating glazing units (IGUs) comprise two or more glass lites (panes)separated by one or more volumes which are sealed and then filled withan insulating gas mixture and/or partially evacuated to create at leastone insulating cavity. Vacuum insulating glazing units (VIGUs) comprisetwo or more glass lites separated by one or more volumes which aresealed and evacuated to create at least one insulating vacuum cavity.The volume between the lites is sealed around its perimeter (or edge) byan edge seal. The edge seal is a part (or assembly of parts) that isbonded to one lite, spans across the gap between the two lites, and isbonded to the second lite. At any time after the IGU/VIGU has beenassembled, the first lite may have a difference in temperature from thesecond lite. The temperature difference leads to differential expansionor contraction and, therefore, relative motion between the glass lites.A rigid edge seal strongly resists the relative motion between thelites, thereby creating a buildup of thermal stresses within theIGU/VIGU assembly. A need therefore exists, for a compliant edge sealthat permits relative motion between the glass lites, thereby reducingthe stresses created in the IGU/VIGU assembly due to thermaldistortions. Minimization of the thermal stresses is desirable toprevent IGU/VIGU failure in climates where significant temperaturedifferences between adjacent lites are encountered.

The relative motion between adjacent lites in any region along theperimeter of the IGU/VIGU can be broken into two components, both ofwhich are oriented parallel to the planes of the lites. The relativemotion normal to the planes of the lites is relatively small, and istherefore not included. The two components parallel to the planes of thelites are herein defined relative to the edge seal. The motion componentoriented along the length of any portion of the edge seal is hereindefined as the longitudinal component and the motion component orientedat a right angle (i.e., normal) to the longitudinal component andparallel to the planes of the lites is herein defined as the lateralcomponent. At any given point around the perimeter of the IGU/VIGUassembly, there are generally longitudinal and lateral components ofrelative motion between the lites at any given time. The relative motionis believed to be largest near the corners in the case of a rectangularIGU/VIGU. A need therefore exists, for an edge seal that offerscompliance in both the longitudinal and lateral directions.

The edge seal for an IGU/VIGU is generally constructed of a thin sheetof material. For VIGUs, the edge seal must be hermetic, and thus isgenerally constructed of a thin hermetic sheet of material. The sheetmaterial is formed in some fashion around the edge of the IGU/VIGU. Thegeometry of the edge seal dictates that relative motion of the lites inthe longitudinal direction is largely accommodated by a shearing actionof the edge seal while relative motion of the lites in the lateraldirection is largely accommodated by bending of the edge seal material.Thin sheet material is relatively rigid in response to a shearing actionand relatively compliant in response to a bending action. As a result,longitudinal (shear) compliance is generally more difficult to obtainthan lateral (bending) compliance in an IGU/VIGU edge seal when the edgeseal is formed of a thin sheet of material. A need therefore exists, foran edge seal having improved longitudinal (shear) compliance.

SUMMARY

This disclosure describes edge seals for IGUs and/or VIGUs that arehighly compliant in response to longitudinal and lateral components ofrelative motion between the two adjacent lites attached to one anotherthrough the edge seal.

In one embodiment, an insulating glazing unit comprises a first liteformed from a hermetic transparent material and a second lite formedfrom a hermetic transparent material and spaced-apart from the firstlite to define an insulating cavity therebetween. An edge seal ishermetically bonded between the respective edges of the first lite andthe second lite, the edge seal being formed from a hermetic material.The edge seal includes a compliant region having a surface formed in athree-dimensional pattern.

In another embodiment, an insulating glazing unit comprises a first liteformed from a hermetic transparent material and a second lite formedfrom a hermetic transparent material that is spaced-apart from the firstlite to define an insulating cavity therebetween. An edge seal assemblyincludes an outer member, a first inner member and a second innermember, each of the outer member, first inner member and second innermember being formed of hermetic materials. An inner surface of firstinner member is hermetically bonded to an outer edge of the first lite,an inner surface of second inner member is hermetically bonded to anouter edge of the second lite, the outer surface of the first innermember is hermetically bonded to a first inner edge of the outer member,and the outer surface of the second inner member is hermetically bondedto a second inner edge of the outer member. The edge seal includes acompliant region having a surface formed in a three-dimensional pattern.

In another embodiment, a method of manufacturing an insulating glazingunit is provided. The method comprises the following steps: a) providinga length of first inner member, wrapping the length of inner memberaround a first lite, cutting and joining the first inner member toitself at the location where it would otherwise overlap itself, andjoining the first inner member to the edge of the first lite where it iscoincident after wrapping; b) providing a length of second inner member,wrapping the length of inner member around a second lite, cutting andjoining the second inner member to itself at the location where it wouldotherwise overlap itself, and joining the second inner member to theedge of the second lite where it is coincident after wrapping; c)positioning the first lite and the second lite in a spaced-apartconfiguration forming an insulating cavity; d) providing a length of anouter member having a compliant region with a three-dimensional surfacepattern, wrapping the outer member around the assembly of first andsecond lites and first and second inner members, cutting and joining theouter member to itself at the location where it would otherwise overlapitself and joining the outer member to each one of the inner members toform a pair of continuous seals; and e) evacuating the insulating cavityand sealing the insulating cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding, reference is now made to thefollowing description taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is a cross-sectional perspective view of a VIGU/IGU having anedge seal;

FIG. 2 is a cross-sectional perspective view of a VIGU/IGU having anedge seal with a compliant region including a three-dimensional patternimprinted thereon in accordance with another embodiment;

FIGS. 3a and 3b are enlarged perspective views of the compliant regionof the edge seal of FIG. 2, wherein FIG. 3a shows the unstressed(un-deformed) state and FIG. 3b shows the shear (i.e., longitudinally)deformed shape;

FIGS. 4a and 4b are perspective and side views, respectively, of thecompliant region of FIG. 2;

FIGS. 5a and 5b are perspective and side views, respectively, of analternative three-dimensional pattern for a compliant region inaccordance with another embodiment;

FIGS. 6a and 6b are perspective and side views, respectively, of analternative three-dimensional pattern for a compliant region inaccordance with yet another embodiment;

FIGS. 7a, 7b and 7c are cross-sectional perspective views of anotherVIGU/IGU in accordance with an apparatus and a method in accordance withadditional embodiments;

FIG. 8 is a perspective view of the corner of a VIGU/IGU similar to thatshown in FIGS. 7a, 7b and 7 c;

FIGS. 9a and 9b are cross-sectional perspective views of a VIGU/IGU inaccordance with another embodiment, FIG. 9a showing the edge seal withthe three-dimensional pattern omitted for purposes of illustration andFIG. 9b showing the edge seal with the location of the three-dimensionalpattern indicated by checkerboard markings;

FIGS. 10a and 10b are cross-sectional perspective views of a VIGU/IGU inaccordance with another embodiment, FIG. 10a showing the edge seal withthe three-dimensional pattern omitted for purposes of illustration andFIG. 10b showing the edge seal with the location of thethree-dimensional pattern indicated by checkerboard markings;

FIGS. 11a and 11b are cross-sectional perspective views of a VIGU/IGU inaccordance with another embodiment, FIG. 11a showing the edge seal withthe three-dimensional pattern omitted for purposes of illustration andFIG. 11b showing the edge seal with the location of thethree-dimensional pattern indicated by checkerboard markings;

FIGS. 12a and 12b are cross-sectional perspective views of a VIGU/IGU inaccordance with another embodiment, FIG. 12a showing the edge seal withthe three-dimensional pattern omitted for purposes of illustration andFIG. 12b showing the edge seal with the location of thethree-dimensional pattern indicated by checkerboard;

FIGS. 13a, 13b, 13c and 13d are cross-sectional side views of a VIGU/IGUin accordance with another embodiment having a single piece edge seal;FIG. 13a showing the edge seal after formation of the three-dimensionalpattern, FIG. 13b showing the edge seal positioned adjacent the twoglass panes for a first bond, FIG. 13c showing the edge seal positionedadjacent the two glass panes for a second bond and FIG. 13d showing thecompleted VIGU/IGU;

FIGS. 14a, 14b, 14c and 14d are cross-sectional side views of a VIGU/IGUin accordance with an alternative embodiment having a single piece edgeseal; FIG. 14a showing the edge seal after formation of thethree-dimensional pattern, FIG. 14b showing the edge seal positionedadjacent the two glass panes for a first bond, FIG. 14c showing the edgeseal positioned adjacent the two glass panes for a second bond and FIG.14d showing the completed VIGU/IGU;

FIG. 15 is a perspective view of a corner portion of a VIGU/IGU havinglarge-radius corners showing one configuration of an edge seal in thecorner region;

FIG. 16 is a perspective view of a corner portion of another VIGU/IGUhaving large-radius corners showing an alternative configuration of anedge seal in the corner region;

FIG. 17 is a perspective view of a corner portion of a VIGU/IGU havingsharp-radius corners showing one configuration of an edge seal in thecorner region;

FIG. 18 is a perspective view of a corner portion of another VIGU/IGUhaving sharp-radius corners showing an alternative configuration of anedge seal in the corner region; and

FIGS. 19a, 19b, 19c, 19d and 19e are perspective views illustrating thefabrication of a metal edge band and its attachment to a glass pane inaccordance with another embodiment; FIG. 19a showing the metal edge bandbeing extended from a supply reel, FIG. 19b showing the fabrication ofthe edge seal end, FIG. 19c showing the welding of the edge band; FIG.19d showing the stretching/positioning of the edge band and FIG. 19eshowing the glass pane with the edge band attached.

DETAILED DESCRIPTION

Referring now to the drawings, wherein like reference numbers are usedherein to designate like elements throughout, the various views andembodiments of a method and apparatus for an insulating glazing unit andcompliant seal for an insulating glazing unit are illustrated anddescribed, and other possible embodiments are described. The figures arenot necessarily drawn to scale, and in some instances the drawings havebeen exaggerated and/or simplified in places for illustrative purposesonly. One of ordinary skill in the art will appreciate the many possibleapplications and variations based on the following examples of possibleembodiments.

For purposes of this application, the term “hermetic” as applied to amaterial or a seal shall mean (unless otherwise specifically denoted)that, when used to form a sealed cavity and subjected to a pressuredifferential of approximately one atmosphere (i.e., in air), thematerial or seal has a permeability or “leak rate” that is sufficientlylow such that the internal pressure within the sealed cavity changes byless than 1 mtorr (i.e., 1×10⁻³ torr) over a period of at least tenyears, and preferably over a period of 30-40 years. For example, if theinitial pressure within the sealed cavity is 1×10⁻⁴ torr, the materialsand/or seals forming the cavity would be considered hermetic for tenyears if the pressure within the sealed cavity after ten years is stillless than 1.1×10⁻³ torr. In another example, if the initial pressurewithin the sealed cavity is 5×10⁻⁵ torr, the materials and/or sealsforming the cavity would be considered hermetic for thirty years if thepressure within the sealed cavity after thirty years is less than1.05×10⁻³ torr.

Referring now to FIG. 1, there is illustrated a cross-sectional view ofa vacuum insulating glazing unit (VIGU). VIGU 100 comprises a first lite101 and a second lite 102. The lites are formed from a hermetictransparent material, preferably glass. Lites 101 and 102 arespaced-apart from one another, defining an insulating cavity 103therebetween. A plurality of stand-off members or “spacers” (not shown)may be positioned in the cavity 103 between the lites 101 and 102 tomaintain separation of the lites. The stand-off members may be affixedto one or both of the lites 101, 102 or held in place by other means,e.g., suspended on fibers or held in position by friction between thelites. The stand-off members may be formed of glass, ceramic, metal orother materials having high compression strength and little or noout-gassing. An edge seal 104 is hermetically bonded between therespective edges of first lite 101 and second lite 102 using a hermeticjoining material 105. In the embodiment shown, the edge seal 104 isbonded to the upper surface of first lite 101 and to the lower surfaceof second lite 102. In an alternative embodiment, the edge seal 104 ishermetically bonded to the upper front edge of first lite 101 (e.g., inthe area denoted 105 a) and to the lower front edge of second lite 102(e.g., in the area denoted 105 b). In another alternative embodiment,the edge seal 104 is hermetically bonded directly to the lites 101 and102 such that joining material 105 is not necessary. The edge seal 104is formed from a hermetic material, preferably a foil or thin sheet ofmetal or metal alloy. Lateral motion of lite 101 relative to lite 102 isdenoted by the arrow 106, and longitudinal motion of lite 101 relativeto lite 102 is denoted by the arrow 107. In a VIGU, the insulatingcavity is evacuated to a vacuum. In one embodiment, the hermeticmaterials are hermetic for at least ten years. In another embodiment,the hermetic materials are hermetic for at least thirty years. In yetanother embodiment, the hermetic materials are hermetic for at leastforty years. In a preferred embodiment, the insulating cavity isevacuated to a vacuum within the range from 1×10⁻⁶ torr to 1×10⁻³ torr.Alternatively, an insulating glazing unit (IGU) (not shown) may beconstructed in a substantially identical fashion, except the materialsand seals need not be hermetic and the atmosphere within the insulatingcavity is a partial vacuum and/or filled with an insulating gas or gasmixture. The evacuation, partial evacuation or (in the case of IGUs)filling with insulating gasses of the insulating cavity may be achievedby sealing the insulating cavity while the VIGU/IGU is in, respectively,a vacuum chamber, a partial vacuum chamber or a gas-filled chamber.Alternatively, the evacuation and/or filling may be achieved after theinsulating cavity has been sealed via an evacuation port (also called a“pinch-off tube” or “pump-out tube”) in communication with theinsulating cavity.

Referring now to FIG. 2, there is illustrated a cross-sectional view ofa VIGU in accordance with one embodiment. Except as noted below, VIGU200 is generally similar to VIGU 100 shown in FIG. 1, comprising a firstlite 201, a second lite 202, an insulating cavity 203 therebetween andan edge seal 204 bonded between the respective edges of first lite 201and second lite 202 using a hermetic joining material 205. The lites 201and 202 are formed from a hermetic transparent material, preferablyglass. A plurality of stand-off members (not shown) may be positioned inthe cavity 203 between the lites 201 and 202 to maintain separation ofthe lites. The stand-off members may be affixed to one or both of thelites 201, 202 or held in place by other means. The stand-off membersmay be formed of glass, ceramic, metal or other materials having highcompression strength and little or no out-gassing. The edge seal 204 isformed from a hermetic material, preferably a foil or thin sheet ofmetal or metal alloy. In the embodiment shown, the edge seal 204 isbonded to the upper surface of first lite 201 and to the lower surfaceof second lite 202. In an alternative embodiment, the edge seal 204 ishermetically bonded to the upper front edge of first lite 201 (e.g., inthe area denoted 205 a) and to the lower front edge of second lite 202(e.g., in the area denoted 205 b). In another alternative embodiment,the edge seal 204 is hermetically bonded directly to the lites 201 and202 such that joining material 205 is not necessary.

The edge seal 204 of VIGU 200 includes a compliant region 208 having asurface formed in a three-dimensional pattern. The three-dimensionalpattern of the compliant region 208 may be formed by imprinting,stamping, embossing, roll-forming or other known methods ofmetal-forming. The compliant region 208 provides greater compliance tothe edge seal 204 to accommodate relative motion between the lites 201and 202 in the lateral direction (denoted by arrow 206) and/or in thelongitudinal directions (denoted by arrow 207), as compared to edgeseals without the three-dimensional compliant region. This greatercompliance may result in a reduction of thermally-induced stress in thelites 201 and 202, e.g., in the area where the edge seal 204 is bondedto the lites, as well as in the compliant edge seal itself. In theembodiment illustrated in FIG. 2, the compliant region 208 of the edgeseal is bounded on two sides by relatively flat, longitudinally-orientedregions 209 of the edge seal lying substantially in the same plane asthe compliant region. In a VIGU, the insulating cavity is evacuated to avacuum. In one embodiment, the hermetic materials are hermetic for atleast ten years. In another embodiment, the hermetic materials arehermetic for at least thirty years. In yet another embodiment, thehermetic materials are hermetic for at least forty years. In a preferredembodiment, the insulating cavity is evacuated to a vacuum within therange of 1×10⁻⁶ torr to 1×10⁻³ torr. Alternatively, an insulatingglazing unit (IGU) (not shown) may be constructed in a substantiallyidentical fashion, except the materials and seals need not be hermeticand the atmosphere within the insulating cavity is a partial vacuumand/or filed with an insulating gas or gas mixture. As describe above,the evacuation, partial evacuation or (in the case of IGUs) filling withinsulating gasses of the insulating cavity may be achieved at the timeof sealing the insulating cavity by sealing it while the VIGU/IGU is in,respectively, a vacuum chamber, a partial vacuum chamber or a gas-filledchamber. Alternatively, the evacuation and/or filling of the insulatingcavity may be achieved after the insulating cavity has been sealed viaan evacuation port.

Referring now to FIGS. 3a and 3b , there is illustrated an enlargedportion of the compliant region 208 of edge seal 204, showing how asheet material 300 having a three-dimensional imprinted patternaccommodates shear deformation largely through bending of thethree-dimensional sheet material rather than extension (i.e., overallstretching) of the sheet material. In other words, as thethree-dimensional sheet material is subjected to stresses, thethree-dimensional contours of the sheet material can bend in localizedareas (e.g., at the junctions between the “hills” and “valleys” of thepattern) from their initial configuration into a longer, flatterconfiguration in regions subjected to tension and into a shorter, morecontoured configuration in regions subjected to compression.

Specifically, FIG. 3a shows compliant region 208 in a non-deformed(i.e., unloaded) shape 301, whereas FIG. 3b shows compliant region 208being deformed into a shear-deformed shape 302 by the application ofloads in opposite directions (denoted by arrows 303). In thisembodiment, the arrows 303 indicate a loading direction consistent withrelative motion between lites 201 and 202 in the longitudinal direction207; however, loading in the lateral direction or in both directions ispossible. It will be appreciated that the contour lines appearing inFIGS. 3a and 3b are for purposes of illustration, i.e., to allowvisualization of the surface contours of compliant region 208, and donot represent actual indicia or structures on the sheet material 300. Iffor use in a VIGU, the sheet material 300 is formed from a hermeticmaterial, preferably a foil or thin sheet of metal or metal alloy. Inone embodiment, the hermetic materials are hermetic for at least tenyears. In another embodiment, the hermetic materials are hermetic for atleast thirty years. In yet another embodiment, the hermetic materialsare hermetic for at least forty years. If for use in an IGU, the sheetmaterial 300 need not be a hermetic material.

Referring now to FIGS. 4a and 4b , there is further illustrated a sheetmaterial 400 having a three-dimensional imprinted pattern 401 suitablefor use on the compliant region 208 of edge seal 204. Specifically, FIG.4a is an isometric view of the sheet material 400 and FIG. 4b is a sideview of the sheet material 400 having the same pattern 401.

Referring now to FIGS. 5a and 5b , there is illustrated an alternativesheet material 500 having a three-dimensional imprinted pattern 501suitable for use on the compliant region 208 of edge seal 204.Specifically, FIG. 5a is an isometric view of the sheet material 500 andFIG. 5b is a side view of the sheet material 500 having the same pattern501.

Referring now to FIGS. 6a and 6b , there is illustrated anotheralternative sheet material 600 having a three-dimensional imprintedpattern 601 suitable for use on the compliant region 208 of edge seal204. Specifically, FIG. 6a is an isometric view of the sheet material600 and FIG. 6b is a side view of the sheet material 600 having the samepattern 601.

Referring now to FIGS. 7a, 7b and 7c , there is illustrated a VIGU/IGUin accordance with another embodiment and a method of obtaininglongitudinal compliance using a three-dimensional patterned edge seal inaccordance with yet another embodiment. Specifically, FIG. 7a shows aVIGU/IGU 700 after assembly, FIG. 7b is an exploded diagram of thecomponents of VIGU/IGU 700 prior to assembly, and FIG. 7c shows theVIGU/IGU 700 at an intermediate stage during the assembly process. TheVIGU/IGU 700 includes a first lite 701 and second lite 702 spaced apartto define an insulating (e.g., vacuum, partial vacuum or insulatinggas-filled) cavity 703 disposed therebetween. A plurality of stand-offmembers (not shown) may be positioned in the cavity 703 between thelites 701 and 702 to maintain separation of the lites. The stand-offmembers may be affixed to one or both of the lites 701, 702 or held inplace by other means, e.g., suspended on fibers or held in position byfriction between the lites. The lites 701 and 702 are formed from ahermetic transparent material, preferably glass. The stand-off membersmay be formed of glass, ceramic, metal or other materials having highcompression strength and little or no out-gassing. As further describedbelow, an edge seal assembly 705 having a compliant portion is bondedbetween the respective edges of the two lites 701 and 702.

As best seen in FIG. 7b , the edge seal assembly 705 includes an outermember 704, a first inner member 709 and a second inner member 710. Aninner surface 711 of first inner member 709 is bonded to an outer edge713 of the first lite 701, and an inner surface 712 of second innermember 710 is bonded to an outer edge 714 of the second lite 702. In thecase of a VIGU, the bonds between inner member inner surfaces 711, 712and respective lite outer edges 713, 714 are hermetic. The outer surface715 of the first inner member 709 is bonded to a first inner edge 717 ofthe outer member 704, and the outer surface 716 of the second innermember 710 is bonded to a second inner edge 718 of the outer member. Inthe case of a VIGU, the bonds between inner member outer surfaces 715,716 and respective outer member inner edges 717, 718 are hermetic. Theouter member 704 includes a compliant region 720 having a surface formedin a three-dimensional pattern, e.g., the three-dimensional patternspreviously described in connection with FIGS. 2, 3 a, 3 b, 4 a, 4 b, 5a, 5 b, 6 a and/or 6 b. Preferably, some or all of the edge sealelements 704, 709 and 710 are spoolable parts, meaning they may bestored in a rolled-up state on a spool until needed for assembly.

In a VIGU, the insulating cavity is evacuated to a vacuum. In oneembodiment, the hermetic materials are hermetic for at least ten years.In another embodiment, the hermetic materials are hermetic for at leastthirty years. In yet another embodiment, the hermetic materials arehermetic for at least forty years. In a preferred embodiment, theinsulating cavity is evacuated to a vacuum within the range of 1×10⁻⁶torr to 1×10⁻³ torr. Alternatively, an insulating glazing unit (IGU)(not shown) may be constructed in a substantially identical fashion,except the materials and seals need not be hermetic and the atmospherewithin the insulating cavity is a partial vacuum and/or filed with aninsulating gas or gas mixture. As describe above, the evacuation,partial evacuation or (in the case of IGUs) filling with insulatinggasses of the insulating cavity may be achieved at the time of sealingthe insulating cavity by sealing it while the VIGU/IGU is in,respectively, a vacuum chamber, a partial vacuum chamber or a gas-filledchamber. Alternatively, the evacuation and/or filling of the insulatingcavity may be achieved after the insulating cavity has been sealed via apinch-off tube or pump-out tube.

As best seen in FIG. 7c , after bonding the inner surface 711 of firstinner member 709 to the outer edge 713 of the first lite 701, the innersurface 712 of second inner member 710 to the outer edge 714 of thesecond lite 702, the outer surface 715 of the first inner member 709 tothe first inner edge 717 of the outer member 704, and the outer surface716 of the second inner member 710 to the second inner edge 718 of theouter member, the flange portions 721, 722 of the edge seal assembly 705may be folded back approximately 90 degrees (as denoted by arrows 723)such that they lie against the outer surfaces of the lites 701, 702. Inthe case where the flange portions 721, 722 are folded such that theylie against the outer surfaces of the lites 701, 702, it is preferredthat the flanges are also joined to the surfaces of the lites, e.g., byadhesive, solder or other adherent materials. Note, however, thisjoining of the flanges to the lites need not be hermetic.

As seen in FIGS. 7a, 7b and 7c , one method of assembling a VIGU/IGU 700is to take the following numbered steps: 1) Unload (e.g., unspool ifstored on a spool) a length of first inner member 709; wrap the lengthof inner member 709 around first lite 701, cut and join member 709 toitself at the location where it would otherwise overlap itself; and joinmember 709 to the edge 713 of lite 701 where it is coincident afterwrapping. 2) Unload (e.g., unspool if stored on a spool) a length ofsecond inner member 710; wrap the length of inner member 710 aroundsecond lite 702, cut and join member 710 to itself at the location whereit would otherwise overlap itself; and join member 710 to the edge 714of lite 702 where it is coincident after wrapping. 3) Position firstlite 701 and second lite 702 in a spaced-apart configuration forming thecavity 703 and including any other assembly parts such as spacers (notshown) between the lites 701, 702. 4) Unload (e.g., unspool if stored ona spool) a length of outer member 704 having a compliant region 720 witha three-dimensional surface pattern; wrap the outer member 704 aroundthe assembly of lites 701, 702 and inner members 709, 710; cut and joinouter member 704 to itself at the location where it would otherwiseoverlap itself and join outer member 704 to one of the inner members 709and 710 where it is coincident after wrapping. 5) Place the assembly ina vacuum chamber to evacuate the vacuum cavity 703 and seal the vacuumcavity by joining outer member 704 to the remaining inner member 709 or710 where it is coincident. In an alternative method, step 5) above maybe replaced with step 5a) as follows: 5a) Seal the vacuum cavity byjoining outer member 704 to the remaining inner member 709 or 710 whereit is coincident; then evacuating the vacuum cavity 703 via anevacuation port; and then sealing the evacuation port.

Referring now to FIG. 8, there is illustrated a VIGU/IGU assembly 800similar to the VIGU/IGU 700 depicted in FIGS. 7a, 7b and 7c , butshowing how the compliant edge-seal 705 with compliant,three-dimensional patterned region 720 could be wrapped around thecorners of the VIGU/IGU. The first and second inner members 709, 710 arefirst joined, respectively, to the first and second lites 701, 702(including the corners of the lites) as previously described. Next, theouter member 704 is joined to the inner members 709, 710 (includingaround the corners) as previously described. Finally, the edge sealflanges 721, 722 are folded down such that they lie against the outersurfaces of the lites 701, 702 and then joined to the surfaces of thelites as previously described. It will be appreciated that the portionsof the flanges 721, 722 wrapped around the corners of the lites mayincur creases as they are folded back against the surface of the lites701, 702, however, these creases do not compromise the sealing functionof the seal assembly 705 as the joint created between the respectivesealing surfaces 711, 712 of inner members 709, 710 and the edges 713,714 of the lites prior to folding remains a continuous joint free ofcreasing.

Referring now to FIGS. 9a and 9b , there is illustrated a VIGU/IGU 900with an alternative edge seal configuration 905 that can accommodate thedisclosed method of obtaining longitudinal compliance through the use ofa three-dimensional imprinted pattern. Specifically, FIG. 9a shows theedge seal 905 with the three-dimensional pattern of the compliant region920 not shown for purposes of clearly illustrating the sealconfiguration; whereas FIG. 9b shows the same VIGU/IGU 900 with thelocation of the compliant region 920 indicated by use of a checkerboardpattern. Seal 905 is a bellows type seal. The compliant region 920 mayuse any of the three-dimensional patterns previously described herein.

Referring now to FIGS. 10a and 10b , there is illustrated a VIGU/IGU1000 with an alternative edge seal configuration 1005 that canaccommodate the disclosed method of obtaining longitudinal compliancethrough the use of a three-dimensional imprinted pattern. Specifically,FIG. 10a shows the edge seal 1005 with the three-dimensional pattern ofthe compliant region 1020 not shown for purposes of clearly illustratingthe seal configuration; whereas FIG. 10b shows the same VIGU/IGU 1000with the location of the compliant region 1020 indicated by use of acheckerboard pattern. Seal 1005 is a flat seal. The compliant region1020 may use any of the three-dimensional patterns previously describedherein.

Referring now to FIGS. 11a and 11b , there is illustrated a VIGU/IGU1100 with an alternative edge seal configuration 1105 that canaccommodate the disclosed method of obtaining longitudinal compliancethrough the use of a three-dimensional imprinted pattern. Specifically,FIG. 11a shows the edge seal 1105 with the three-dimensional pattern ofthe compliant region 1120 not shown for purposes of clearly illustratingthe seal configuration; whereas FIG. 11b shows the same VIGU/IGU 1100with the location of the compliant region 1120 indicated by use of acheckerboard pattern. Seal 1105 is similar to the embodiment describedin connection with FIGS. 7a, 7b and 7c , except there is an extraconvolution 1110 in the geometry which may further increase longitudinalcompliance and further increase the thermal resistance through the edgeseal. The compliant region 1120 may use any of the three-dimensionalpatterns previously described herein.

Referring now to FIGS. 12a and 12b , there is illustrated a VIGU/IGU1200 with an alternative edge seal configuration 1205 that canaccommodate the disclosed method of obtaining longitudinal compliancethrough the use of a three-dimensional imprinted pattern. Specifically,FIG. 12a shows the edge seal 1205 with the three-dimensional pattern ofthe compliant region 1220 not shown for purposes of clearly illustratingthe seal configuration; whereas FIG. 12b shows the same VIGU/IGU 1200with the location of the compliant region 1220 indicated by use of acheckerboard pattern. Seal 1205 is another type of flat seal. Thecompliant region 1220 may use any of the three-dimensional patternspreviously described herein.

Referring now to FIGS. 13a, 13b, 13c and 13d , there is illustrated aVIGU/IGU 1300 having a one-piece edge seal in accordance with anotherembodiment, and a method of producing a VIGU/IGU having a one-piece edgeseal in accordance with yet another embodiment. Specifically, FIG. 13ashows a cross-sectional view of a one-piece edge seal 1305 comprising acentral compliant portion 1320 disposed between two lateral portions1322. The edge seal 1305 may be formed from a hermetic material,preferably a foil or thin sheet of metal or metal alloy that can besoldered and/or welded. Preferably, the material of the edge seal 1305is spoolable, i.e., it may be stored in a rolled-up state on a spool (orreel) until needed for assembly.

The compliant portion 1320 of the edge seal 1305 may have a surfaceformed in a three-dimensional pattern, e.g., the three-dimensionalpatterns previously described in connection with FIGS. 2, 3 a, 3 b, 4 a,4 b, 5 a, 5 b, 6 a and/or 6 b. Each lateral portion 1322 includes aproximal section 1324 disposed adjacent to the central compliant portion1320 and a distal section 1326 disposed on the opposite side of theproximal section from the compliant portion.

Referring now to FIG. 13b , the one-piece edge seal 1305 is positionedso that the compliant portion 1320 lies adjacent a first lite 1301 andsecond lite 1302, which are spaced apart to define an insulating cavity1303 disposed therebetween (which will later be evacuated). Inparticular, the compliant portion 1320 is aligned with edges 1313 and1314, respectively, of the lites 1301 and 1302. The lites 1301 and 1302are formed from a hermetic transparent material, preferably glass. Aplurality of stand-off members 1325 (FIG. 13d ) may be positioned in thecavity 1303 between the lites 1301 and 1302 to maintain separation ofthe lites. For purposes of illustration, the stand-off members 1325 arenot shown in FIGS. 13b and 13c . The stand-off members may be affixed toone or both of the lites 1301, 1302 or held in place by other means,e.g., suspended on fibers or held in position by friction between thelites. The stand-off members 1325 may be formed of glass, ceramic, metalor other materials having high compression strength and little or noout-gassing.

Referring still to FIG. 13b , each lateral portion 1322 of the edge seal1305 is first folded between the proximal section 1324 and the distalsection 1326 to bring at least a first part of the distal sectiondirectly adjacent to the edges 1313 and 1314 of the lites 1301 and 1302,i.e., interposed between the edges 1313, 1314 and the compliant portion1320. As further described herein, each first part of the distal section1326 of the edge seal 1305 is then bonded to the respective adjacentedge 1313, 1314 of the lites 1301, 1302 to form a hermetic bond 1330(FIG. 13d ). The hermetic bond 1330 must be capable of blocking thepassage of gasses into the cavity 1303 to maintain the requiredhermeticity, but it is not required to withstand any significantstructural loads arising from the compliant portion 1320 of the edgeseal 1305. In some embodiments, the hermetic bond 1330 comprises asolder. In preferred embodiments, the solder is a metallic solder,however, in other embodiments the solder may be a solder glass.

Referring now to FIG. 13c , after hermetically bonding the first part ofeach distal section 1326 to the edges 1313, 1314, the lateral portion1322 is folded a second time such that the remaining parts of the distalsection lie against the respective faces 1327, 1328 of lites 1301, 1302and the proximal portions 1324 lie substantially parallel to the faces.As further described herein, each remaining part of the distal section1326 of the edge seal 1305 is then bonded to the respective adjacentface 1327, 1328 to form a structural bond 1332 (FIG. 13d ). Thestructural bond 1332, unlike the hermetic bond 1330, need not be capableof blocking the passage of gasses into the cavity 1303. Instead, thestructural bond 1332 must withstand the structural loads arising fromthe compliant portion 1320 and prevent the transmission of anysignificant structural loads to the hermetic bond 1330. Accordingly, thestructural bond 1332 is always interposed along the edge seal 1305between the compliant portion 1320 and the hermetic bond 1330 (i.e.,when considering the edge seal 1305 as extending continuously from onedistal end to the opposite distal end). In some embodiments, thestructural bond 1332 may comprise one of a thermoset or a thermoplastic.In preferred embodiments, the structural bond 1332 may comprise one ormore of acrylic, epoxy, urethane, polyester, polyimide, phenolic,polyamide, cyanoacrylate, polyacrylate, and polyvinyl acetate.

Referring now to FIG. 13d , the VIGU 1300 is shown, including the lites1301, 1302, edge seal 1305 and stand-off members 1325 (for purposes ofillustration, only an end portion of the complete VIGU is shown). Theinsulating cavity 1303 is evacuated to a vacuum, typically through anevacuation port (not shown) following forming the hermetic bonds 1330and the structural bonds 1332. In one embodiment of the VIGU 1300, thehermetic materials, including the hermetic bond 1330, are hermetic forat least ten years. In another embodiment, the hermetic materials,including the hermetic bond 1330, are hermetic for at least thirtyyears. In yet another embodiment, the hermetic materials, including thehermetic bond 1330, are hermetic for at least forty years. In apreferred embodiment, the insulating cavity 1303 is evacuated to avacuum within the range of 1×10⁻⁶ torr to 1×10⁻³ torr. Alternatively, aninsulating glazing unit (IGU) (not shown) may be constructed in asubstantially identical fashion, except the materials and seals need notbe hermetic and the atmosphere within the insulating cavity is a partialvacuum and/or filed with an insulating gas or gas mixture. As describeabove, the evacuation, partial evacuation or (in the case of IGUs)filling with insulating gasses of the insulating cavity 1303 may beachieved at the time of sealing the insulating cavity by sealing itwhile the VIGU/IGU 1300 is in, respectively, a vacuum chamber, a partialvacuum chamber or a gas-filled chamber. Alternatively, the evacuationand/or filling of the insulating cavity 1303 may be achieved after theinsulating cavity has been sealed via an evacuation tube.

Referring now to FIGS. 14a, 14b, 14c and 14d , there is illustrated aVIGU/IGU 1400 having an alternative one-piece edge seal in accordancewith another embodiment, and a method of producing a VIGU/IGU having analternative one-piece edge seal in accordance with yet anotherembodiment. Specifically, FIG. 14a shows a cross-sectional view of aone-piece edge seal 1405 comprising a central compliant portion 1420disposed between two lateral portions 1422. The edge seal 1405 may beformed from a hermetic material, preferably a foil or thin sheet ofmetal or metal alloy that can be soldered and/or welded. Preferably, thematerial of the edge seal 1405 is spoolable, i.e., it may be stored in arolled-up state on a spool (or reel) until needed for assembly.

The compliant portion 1420 of the edge seal 1405 may have a surfaceformed in a three-dimensional pattern, e.g., the three-dimensionalpatterns previously described in connection with FIGS. 2, 3 a, 3 b, 4 a,4 b, 5 a, 5 b, 6 a and/or 6 b. Each lateral portion 1422 includes aproximal section 1424 disposed adjacent to the central compliant portion1420 and a distal section 1426 disposed on the opposite side of theproximal section from the compliant portion.

Referring now to FIG. 14b , the one-piece edge seal 1405 is positionedso that the compliant portion 1420 lies adjacent a first lite 1401 andsecond lite 1402, which are spaced apart to define an insulating cavity1403 disposed therebetween. In particular, the compliant portion 1420 isaligned with edges 1413 and 1414, respectively, of the lites 1401 and1402. The lites 1401 and 1402 are formed from a hermetic transparentmaterial, preferably glass. A plurality of stand-off members 1425 (FIG.14d ) may be positioned in the cavity 1403 between the lites 1401 and1402 to maintain separation of the lites. The stand-off members may beaffixed to one or both of the lites 1401, 1402 or held in place by othermeans, e.g., suspended on fibers or held in position by friction betweenthe lites. The stand-off members 1425 may be formed of glass, ceramic,metal or other materials having high compression strength and little orno out-gassing.

Referring still to FIG. 14b , each lateral portion 1422 of the edge seal1405 is first folded between the proximal section 1424 and the distalsection 1426 to bring the ends of the distal section near the respectivefaces 1427, 1428 of the lites 1401, 1402. The distal sections 1426 arefurther folded to bring at least a first part 1429 of each distalsection parallel to the faces 1427, 1428 of the lites. As furtherdescribed herein, each first part 1429 of the distal section 1426 isthen bonded to the respective adjacent face 1427, 1428 of the lites1401, 1402 to form a hermetic bond 1430 (FIG. 14d ). The hermetic bond1430 must be capable of blocking the passage of gasses into the cavity1403 to maintain the required hermeticity, but it is not required towithstand any significant structural loads arising from the compliantportion 1420 of the edge seal 1405. In some embodiments, the hermeticbond 1430 comprises a solder. In preferred embodiments, the solder is ametallic solder, however, in other embodiments the solder may be asolder glass.

Referring now to FIG. 14c , after hermetically bonding the first part1429 of each distal section 1426 to the faces 1427, 1428 of the lites1401, 1402, the lateral portion 1422 is folded again such that theremaining parts of the distal section lie substantially parallel to thefaces. As further described herein, a portion of each remaining part ofthe distal section 1426, but not including any portion directlyoverlying the hermetic bond 1430, is then bonded to the respectiveadjacent face 1427, 1428 to form a structural bond 1432 (FIG. 14d ). Thestructural bond 1432, unlike the hermetic bond 1430, need not be capableof blocking the passage of gasses into the cavity 1403. Instead, thestructural bond 1432 must withstand the structural loads arising fromthe compliant portion 1420 and prevent the transmission of anysignificant structural loads to the hermetic bond 1430. Accordingly, thestructural bond 1432 is always interposed along the edge seal 1405between the compliant portion 1420 and the hermetic bond 1430 (i.e.,when considering the edge seal 1405 as extending continuously from onedistal end to the opposite distal end). The structural bond 1432 may beformed of the same materials previously described in connection withstructural bond 1332 of the previous embodiment.

Referring now to FIG. 14d , the VIGU 1400 is shown, including the lites1401, 1402, edge seal 1405 and stand-off members 1425 (again, forpurposes of illustration, only an end portion of the complete VIGU isshown). In one embodiment of the VIGU 1400, the hermetic materials,including the hermetic bond 1430, are hermetic for at least ten years.In another embodiment, the hermetic materials, including the hermeticbond 1430, are hermetic for at least thirty years. In yet anotherembodiment, the hermetic materials, including the hermetic bond 1430,are hermetic for at least forty years. In a preferred embodiment, theinsulating cavity 1403 is evacuated to a vacuum within the range of1×10⁻⁶ torr to 1×10⁻³ torr. Alternatively, an insulating glazing unit(IGU) (not shown) may be constructed in a substantially identicalfashion, except the materials and seals need not be hermetic and theatmosphere within the insulating cavity is a partial vacuum and/or filedwith an insulating gas or gas mixture. As describe above, theevacuation, partial evacuation or (in the case of IGUs) filling withinsulating gasses of the insulating cavity 1403 may be achieved at thetime of sealing the insulating cavity by sealing it while the VIGU/IGU1400 is in, respectively, a vacuum chamber, a partial vacuum chamber ora gas-filled chamber. Alternatively, the evacuation and/or filling ofthe insulating cavity 1403 may be achieved after the insulating cavityhas been sealed via an evacuation tube.

Referring now to FIGS. 15, 16, 17 and 18 there are illustratedperspective views of various VIGU/IGUs 1500, 1600, 1700 and 1800 showingthe seal configuration of the respective edge seals 1502, 1602, 1702 and1802 as they are attached to the corners of the respective glass lites1501, 1601, 1701 and 1801.

A preferred method for forming the hermetic bonds, e.g., the hermeticbonds 1330 or 1430 previously described, is by ultrasonic solderingusing a flux-free solder. Suitable flux-free solder and ultrasonicsoldering equipment are produced by Cerasolzer, for example CerasolzerGS 217 solder or GS 220 solder. In a preferred embodiment, the surfacesof the edge seal and the lites that are to be bonded in the hermeticbond have solder pre-applied (i.e., known as “pre-tinning”). Further, atleast the surfaces to be hermetically bonded, and preferably the entirelites, are preheated to a pre-heat temperature above the solder'sliquidus temperature prior to forming the hermetic bonds.

In one embodiment, the following steps are used: (1) Pre-heat the glasslite and pre-tin the perimeter of the glass lite using ultrasonicsoldering; (2) Pre-tin the inside of the metal edge band that will laterbe wrapped around and soldered to the glass lite; (3) The metal edgeband does not have to be pre-heated but it is preferable to do so beforeultrasonically solder pre-tinning its surface; (4) Use tooling (FIG. 19d) to stretch the pre-tinned metal band so it is large enough to slideonto the perimeter of the now pre-tinned glass; (5) Pre-heat theassembly past the liquid temperature of the solder; and (6) Apply heatand ultrasonic excitation to the metal band to again break any oxides inthe molten solder, moving the hot soldering iron tip all the way aroundthe metal band. If the metal band is elastic enough after stretching,apply the ultrasonic energy to the band where it overlaps the perimeteredge of the glass. Preferably, a compressive fixture is used to hold theedge seal band tight against the perimeter of the pre-tinned glass lite.

Ultrasonic excitation is applied to the part of the metal band thatextends past the edge of the glass and have the band-tensioning fixtureapply the pressure to keep the metal band in very close contact with theglass edge. The band and glass cannot be in intimate contact as we havesolder between the two and want to achieve a hermetic soldered bond orconnection.

Referring now to FIGS. 19a, 19b, 19c, 19d and 19e , an automated processfor applying metal bands around the lite or lites is described that maycomprise the following steps. The glass is cut and the edge is preparedfor solder pre-tinning, if necessary by one of several means. Cleaningmay be required prior to soldering. Smoothing the edge may be requiredto result in less porosity and a more hermetic solder-to-glassinterface. This is an especially important consideration if the glass iscut using a water jet cutter, as the abrasive cutting fluid leavesgrooves horizontal to the two large surfaces of the glass, 90 degrees orperpendicular from the direction one would want if one had to work withsoldering to a grooved perimeter surface. Glass fabricators call theprocess of smoothing the edge of cut glass, “seaming.” Smoothingprocesses are done prior to tempering the glass. These include grinding,sanding, heating such as with a torch to locally melt the glass to forma smooth surface, polishing, and other processes. After any smoothingand cleaning operations, preheat the glass and pre-tin the glass lite'sperimeter. Cut the metal strip 1900 for the edge seal (or edge sealbands) to the correct length (FIG. 19a ), dress the ends 1902 (FIG. 19b) and butt-weld the band together (FIG. 19c ) by TIG, laser or othermeans and then pre-tin the inside of the band where it will come intocontact with the edge of the glass lite 1903. Stretch the completed band1904 (FIG. 19d ) using a stretching fixture 1906 enough to enable theedge seal/band system 1904 to then slide the stretched band over oraround the perimeter of the glass lite 1903 (FIG. 19e ). Next, thebanded assembly 1910 is heated until the flux-free solder is in a liquidstate. Ultrasonic excitation may be applied. Compressive force may beapplied to increase the molten solder's contact area between the metalband and the glass lite. After the metal band 1904 is completelysoldered to the glass lite 1903, the assembly is cooled to roomtemperature, probably with blowing air to decrease the cool-down time.Another way to apply pressure while soldering would be to have one ormore heated rollers apply simultaneous pressure and ultrasonic energy tothe outside of the pre-tinned metal band of the heated assembly and havethe rollers travel around the heated assembly until all the moltensolder has been agitated with appropriate ultrasonic energy.

It will be appreciated by those skilled in the art having the benefit ofthis disclosure that this method and apparatus for an insulating glazingunit and compliant seal for an insulating glazing unit provides aninsulating glazing unit having greatly improved performance andlifespan. It should be understood that the drawings and detaileddescription herein are to be regarded in an illustrative rather than arestrictive manner, and are not intended to be limiting to theparticular forms and examples disclosed. On the contrary, included areany further modifications, changes, rearrangements, substitutions,alternatives, design choices, and embodiments apparent to those ofordinary skill in the art, without departing from the spirit and scopehereof, as defined by the following claims. Thus, it is intended thatthe following claims be interpreted to embrace all such furthermodifications, changes, rearrangements, substitutions, alternatives,design choices, and embodiments.

The invention claimed is:
 1. An insulating glazing unit (IGU) or vacuuminsulating glazing unit (VIGU), comprising: a first lite formed fromhermetic material, the first lite having an outer surface, an innersurface opposite the outer surface, and a peripheral edge surfacedisposed between the outer surface and the inner surface around theperiphery of the first lite; a second lite formed from hermeticmaterial, the second lite having an outer surface, an inner surfaceopposite the outer surface, and a peripheral edge surface disposedbetween the outer surface and the inner surface around the periphery ofthe second lite; an insulating cavity disposed between the first liteand the second lite, whereby the inner surface of the first lite isspaced apart from the inner surface of the second lite to define theinsulating cavity therebetween; and an edge seal formed from hermeticmaterial, the edge seal extending between the first lite and the secondlite to enclose the insulating cavity around the periphery of the IGU orVIGU; wherein the edge seal comprises a first lite bonding portion, asecond lite bonding portion, and a center portion disposed between thefirst lite bonding portion and the second lite bonding portion; thefirst lite bonding portion of the edge seal is hermetically bonded tothe first lite; the second lite bonding portion of the edge seal ishermetically bonded to the second lite; the center portion has athree-dimensional pattern of contours which repeats in a plurality ofdirections along a surface of the center portion; and the surface of thecenter portion is substantially parallel to the peripheral edge surfaceof the first lite and to the peripheral edge surface of the second lite.2. The IGU or VIGU of claim 1, wherein with respect to a longitudinalplane bisecting the insulating cavity between the first lite and thesecond lite, the three-dimensional pattern of contours repeats along thesurface of the center portion in a local direction perpendicular to thelongitudinal plane.
 3. The IGU or VIGU of claim 1, wherein with respectto a longitudinal plane bisecting the insulating cavity between thefirst lite and the second lite, the three-dimensional pattern ofcontours repeats along the surface of the center portion in a localdirection parallel to the longitudinal plane.
 4. The IGU or VIGU ofclaim 1, wherein with respect to a longitudinal plane bisecting theinsulating cavity between the first lite and the second lite, thethree-dimensional pattern of contours repeats along the surface of thecenter portion in a local direction perpendicular to the longitudinalplane and in a local direction parallel to the longitudinal plane. 5.The IGU or VIGU of claim 1, wherein the three-dimensional pattern ofcontours comprises protrusions and depressions with relatively sharp,pointed peaks.
 6. The IGU or VIGU of claim 1, wherein thethree-dimensional pattern of contours comprises protrusions anddepressions with relatively rounded peaks.
 7. The IGU or VIGU of claim1, wherein the three-dimensional pattern of contours comprisesprotrusions and depressions forming multiple rows, whereby theprotrusions of adjacent rows are offset from one another.
 8. The IGU orVIGU of claim 1, wherein the surface of the center portion is providedby a sheet of hermetic material, and the three-dimensional pattern ofprotrusions is imprinted on the sheet of hermetic material.
 9. The IGUor VIGU of claim 1, wherein the center region of the edge seal comprisesat least one convolution, the at least convolution resulting in at leasttwo surfaces of the center region which are substantially parallel tothe peripheral edge surface of the first lite and to the peripheral edgesurface of the second lite, whereby the three-dimensional pattern ofcontours is disposed on each of the at least two surfaces of the centerregion.
 10. The IGU or VIGU of claim 1, wherein the first lite bondingportion of the edge seal is hermetically bonded to the peripheral edgesurface of the first lite, and the second lite bonding portion of theedge seal is hermetically bonded to the peripheral edge surface of thesecond lite.
 11. The IGU or VIGU of claim 10, wherein the first litebonding portion is structurally bonded to the peripheral edge surface ofthe first lite, and the second lite bonding portion is structurallybonded to the peripheral edge surface of the second lite.
 12. The IGU orVIGU of claim 11, wherein a single bond joins the edge seal to the firstlite, and another single bond joins the edge seal to the second lite.13. The IGU or VIGU of claim 10, wherein the first lite bonding portionis structurally bonded to the outer surface of the first lite, and thesecond lite bonding portion is structurally bonded to the outer surfaceof the second lite.
 14. The IGU or VIGU of claim 13, wherein a hermeticbond joining the first lite to the edge seal is disposed between theinsulating cavity and a structural bond joining the first lite to theedge seal, and a hermetic bond joining the second lite to the edge sealis disposed between the insulating cavity and a structural bond joiningthe second lite to the edge seal.
 15. The IGU or VIGU of claim 1,wherein the first lite bonding portion of the edge seal is hermeticallybonded to the outer surface of the first lite, and the second litebonding portion of the edge seal is hermetically bonded to the outersurface of the second lite.
 16. The IGU or VIGU of claim 15, wherein thefirst lite bonding portion is structurally bonded to the outer surfaceof the first lite, and the second lite bonding portion is structurallybonded to the outer surface of the second lite.
 17. The IGU or VIGU ofclaim 16, wherein a single bond joins the edge seal to the first lite,and another single bond joins the edge seal to the second lite.
 18. TheIGU or VIGU of claim 16, wherein a hermetic bond joining the first liteto the edge seal is disposed between the insulating cavity and astructural bond joining the first lite to the edge seal, and a hermeticbond joining the second lite to the edge seal is disposed between theinsulating cavity and a structural bond joining the second lite to theedge seal.
 19. The IGU or VIGU of claim 1, wherein the edge seal isformed of a single piece of material.
 20. The IGU or VIGU of claim 1,wherein the first lite bonding portion is formed from a first innermember, the second lite bonding portion is formed from a second innermember, and the center portion is formed from an outer member, wherebythe outer member is hermetically bonded to each of the first innermember and the second inner member.
 21. The IGU or VIGU of claim 1,wherein the insulating cavity is evacuated to a vacuum within a rangefrom 1×10 torr to 1×10 torr.
 22. The IGU or VIGU of claim 1, wherein thefirst lite is generally rectangular with four radius corners, the secondlite is generally rectangular with four radius corners, and the fourradius corners of the first lite are aligned with the four radiuscorners of the second lite.
 23. The IGU or VIGU of claim 1, furthercomprising a plurality of stand-off members positioned within theinsulating cavity to maintain separation between the first lite and thesecond lite.